WBR3L Module Datasheet

Last Updated on : 2020-08-10 05:56:54download

Product Overview

WBR3L is a low-power embedded WiFi+BLE module that Tuya has developed. It consists of a highly integrated wireless RF chip (RTL8720CF), with an embedded WiFi network protocol stack and varied library functions. With the maximum CPU clock rate of 100MHz, WBR3L also contains a low-power KM4 microcontroller unit (MCU), a WLAN MAC, a 1T1R WLAN module, 256 KB static random-access memory (SRAM), 2 MB flash memory, and extensive peripherals. WBR3L is an RTOS platform that integrates all function libraries of the WiFi MAC and TCP/IP protocols. You can develop embedded WiFi products as required.


  1. Embedded low-power KM4 MCU, which can also function as an application processor; Clock rate: 100MHz
  2. Working voltage: 3.0 to 3.6 V
  3. Peripherals: 9 GPIOs, 1 universal asynchronous receiver/transmitter (UART), and 1 log transmitter
  4. WiFi/BT connectivity
    • 802.11 B/G/N20
    • Channels 1 to 14 at 2.4 Ghz (channels 1 to 11 for US/CA and channels 1 to 13 for EU/CN)
    • Support WEP/WPA/WPA2/WPA2 PSK(AES) security modes
    • Support BLE (Bluetooth Low Energy) 4.2
    • Up to +20 dBm output power in 802.11b mode
    • Support SmartConfig functions for Android and iOS devices
    • Onboard PCB antenna
    • Passed CE and FCC certification
    • Working temperature: -20℃ to 105℃


  • Intelligent building
  • Smart household and home appliances
  • Smart socket and light
  • Industrial wireless control
  • Baby monitor
  • Network camera
  • Intelligent bus

Change History

Serial NumberUpdate DateUpdated ContentVersion after Update
13/21/2020This is the first release.V1.0.0

Module Interfaces

Dimensions and Footprint

WBR3L has two rows of pins with a 2 mm pin spacing. Each row has 8 pins. The WBR3L dimensions are 16±0.35 mm (W)×24±0.35 mm (L) ×2.9±0.15 mm (H). The dimensions of WBR3L are as follows:

WBR3L Module Datasheet

Pin Definition

The definition of interface pins is shown in the following table:

Pin NumberSymbolI/O TypeFunction
1NC/It is pulled up to be compatible with other modules
2A_7I/OGPIOA_7, hardware PWM, IC Pin 21
3ENI/OEnabling pin, which works at the high level and is pulled up and controlled by a user externally
4A_11I/OGPIOA_11, hardware PWM, IC Pin 25
5A_2I/OGPIOA_2, hardware PWM, IC Pin 18
6A_3I/OGPIOA_3, hardware PWM, IC Pin 19
7A_4I/OGPIOA_4, hardware PWM, IC Pin 20
8VCCPPower supply pin (3.3V)
9GNDPPower supply reference ground
10A_12I/OGPIOA_12, hardware PWM, IC Pin 26
11A_16I/OGPIOA_16, UART_Log_TXD, which is used for displaying the module internal information and can be configured as a common GPIO
12A_17I/OGPIOA_17, hardware PWM, IC Pin 38
13A_18I/OGPIOA_18, hardware PWM, IC Pin 39
14A_19I/OGPIOA_19, hardware PWM, IC Pin 40
15RXDI/OGPIOA_13, UART0_RXD, which is used as a user-side serial interface pin
16TXDI/OGPIOA_14, UART0_TXD, which is used as a user-side serial interface pin

Note: P indicates power supply pins and I/O indicates input/output pins.

Electrical Parameters

Absolute Electrical Parameters

ParameterDescriptionMinimum ValueMaximum ValueUnit
TsStorage temperature-40125
VDDPower supply voltage-0.33.6V
Static electricity voltage (human body model)TAMB-25℃-2KV
Static electricity voltage (machine model)TAMB-25℃-0.5KV

Working Conditions

ParameterDescriptionMinimum ValueTypical ValueMaximum ValueUnit
TaWorking temperature-20-105
VDDWorking voltage3.0-3.6V
VILI/O low-level input--0.8V
VIHI/O high-level input2.0--V
VOLI/O low-level output--0.4V
VOHI/O high-level output2.4--V
ImaxI/O drive current--16mA
CpadInput pin capacitance-2-pF

RF Power Consumption

  1. TX power consumption:
SymbolModeAverage ValuePeak Value (Typical Value)Unit
IRF11B 11M6365mA
IRF11G 54M6567mA
IRF11N HT20 MCS76567mA
  1. RX power consumption:
SymbolModeAverage ValuePeak Value (Typical Value)Unit
IRF11B 11M6365mA
IRF11G 54M6567mA
IRF11N HT20 MCS76567mA

Working Power Consumption

Working ModeWorking Status (Ta = 25°C)Average ValuePeak Value (Typical Value)Unit
Quick connection network statusThe module is in the fast network connection state and the WiFi indicator always flashes75324mA
Network connection idle stateThe module is connected to the network and the WiFi indicator is always on64314mA
Network connection operation statusThe module is connected to the network and the WiFi indicator is always on66305mA
Disconnected statusThe module is offline and the WiFi indicator is dark66309mA

RF Parameters

Basic RF Features

Frequency range2.400 to 2.4835 GHz
WiFi standardIEEE 802.11b/g/n (channels 1 to 14)
BLE standardBluetooth 4.2
Data transmission rateData transmission rate
Data transmission rate11g: 6, 9, 12, 18, 24, 36, 48, 54 (Mbps)
Data transmission rate11n: HT20 MCS 0 to 7
Antenna TypePCB antenna with a gain of 1.82 dBi

TX Performance

ParameterMinimum ValueTypical ValueMaximum ValueUnit
Average RF output power, 802.11b CCK Mode, 1 Mbit/s-17.5-dBm
Average RF output power, 802.11g OFDM mode, 54 Mbit/s-14.5-dBm
Average RF output power, 802.11n OFDM mode, MCS7-13.5-dBm
Average RF output power, BLE 4.2, 1 Mbit/s-6.5-dBm
Frequency error-20-20ppm
EVM@802.11b CCK 11Mbps Mode 17.5dBm---10dB
EVM@802.11g OFDM 54Mbps Mode 14.5dBm---29dB
EVM@802.11n OFDM MCS7 Mode 13.5dBm---30dB

RX Performance

ParameterMinimum ValueTypical ValueMaximum ValueUnit
PER<8%, RX sensitivity, 802.11b CCK Mode 1M--91-dBm
PER<10%, RX sensitivity, 802.11g OFDM Mode 54M--75-dBm
PER<10%, RX sensitivity, 802.11n OFDM Mode MCS7--72-dBm
PER<10%, RX sensitivity, BLE 4.2 1M--93-dBm

Antenna Information

Antenna Type

WBR3L uses only an onboard PCB antenna with a gain of 1.82 dBi.

Antenna Interference Reduction

To ensure optimal WiFi performance when the WiFi module uses an onboard PCB antenna, it is recommended that the antenna be at least 15 mm away from other metal parts.

Power-on Sequence and Resetting

Power-on Sequence

The RTL8720CF chip has requirements on the power-on sequence. It is recommended that the voltage rise from 0 to 3.3V within 40mS WBR3L Module Datasheet.

SymbolParameterMinimum ValueTypical ValueMaximum ValueUnit
TPRDY3.3V ready time0.6 20mS
CHIP_ENCHIP_EN ready time0.6 20mS


When designing a plate of a module, you should set a resetting IC at the foot of CHIP_EN in advance. The preferable type of IC is BL8506-27CRO. The module is packaged in the form of SOT23. For solutions to starting a module in some cases, refer to the circuit in the following figure (R30 is preset and cannot be placed).

WBR3L Module Datasheet

Packaging Information and Production Instructions

Mechanical Dimensions

The mechanical dimensions of PCB of WBR3L are 16±0.35 mm (W)×24±0.35 mm (L) ×0.8±0.1 mm (H). The following figure shows mechanical dimensions of WBR3L.

WBR3L Module Datasheet

WBR3L Module Datasheet

Note: The default dimensional tolerance is ±0.35 mm. If you have specific requirements on dimensions, make them clear in the datasheet after communication.

Recommended PCB Layout

The following figure is a schematic diagram of WBR3L which shows how pins correspond to each other.

WBR3L Module Datasheet

WBR3L PCB Layout is shown as belows:

WBR3L Module Datasheet

Pin Header Specifications

WBR3L has two models: WBR3L with pin headers and WBR3L without pin headers. Which one is used depends on actual situations. Dimensions and recommended layout of pin headers are as follows (unit: mm): WBR3L Module Datasheet

Production Instructions

  1. Use an SMT placement machine to mount the stamp hole module that Tuya produces onto the PCB within 24 hours after the module is unpacked and the firmware is burned.If not, vacuum pack the module again. Bake the module before mounting it onto the PCB.

    A. SMT placement equipment

    • Reflow soldering machine
    • Automated optical inspection (AOI) equipment
    • Nozzle with a 6 mm to 8 mm diameter

    B. Baking equipment

    • Cabinet oven
    • Anti-static heat-resistant trays
    • Anti-static heat-resistant gloves
  2. Storage conditions for a delivered module are as follows:

  3. The moisture-proof bag is placed in an environment where the temperature is below 30°C and the relative humidity is lower than 70%.

  4. The shelf life of a dry-packaged product is 6 months from the date when the product is packaged and sealed.
  5. There is a humidity indicator card in the moisture-proof bag as belows: WBR3L Module Datasheet

  6. Bake a module based on HIC status as follows when you unpack the module package:

  7. If the 30%, 40%, and 50% circles are blue, bake the module for 2 consecutive hours.

  8. If the 30% circle is pink, bake the module for 4 consecutive hours.
  9. If the 30% and 40% circles are pink, bake the module for 6 consecutive hours.
  10. If the 30%, 40%, and 50% circles are pink, bake the module for 12 consecutive hours.

  11. Baking settings:

  12. Baking temperature: 125±5°C

  13. Alarm temperature: 130°C
  14. SMT placement ready temperature after natural cooling: < 36°C
  15. The number of drying times: 1
  16. Rebaking condition: The module is not soldered within 12 hours after baking

  17. Do not use SMT to process modules that have been unpacked for more than 3 months. Electroless nickel immersion gold (ENIG) is used for the PCBs. If the solder pads are exposed to the air for more than 3 months, they will be oxidized severely and dry joints or solder skips may occur. Tuya is not liable for such problems and consequences.

  18. Before SMT placement, take electrostatic discharge (ESD) protective measures.
  19. To reduce the reflow defect rate, draw 10% of the products for visual inspection and AOI before the first SMT placement to determine proper methods for controlling the oven temperature and attaching and placing components. Draw 5 to 10 modules from subsequent batches each hour for visual inspection and AOI.

Recommended Oven Temperature Curve

Perform SMT placement based on the following reflow oven temperature curve. The highest temperature is 245°C. The reflow temperature curve is shown as belows: Refer to IPC/JEDEC standard; Peak Temperature: <245℃; The number of Times: ≤ 2 times WBR3L Module Datasheet

Storage Conditions

WBR3L Module Datasheet

MOQ and Packaging Information

Product NumberMOQ (pcs)Shipping packaging methodThe number of modules per reel (pcs)The number of reels per carton (reel)
WBR3L3600Tape reel9004


FCC Caution: Any changes or modifications not expressly approved by the party responsible for compliance could void the user's authority to operate this equipment. This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation. This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules.These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures: - Reorient or relocate the receiving antenna. - Increase the separation between the equipment and receiver. - Connect the equipment into an outlet on a circuit different from that to which the receiver is connected. - Consult the dealer or an experienced radio/TV technician for help.

Radiation Exposure Statement This equipment complies with FCC radiation exposure limits set forth for an uncontrolled rolled environment. This equipment should be installed and operated with minimum distance 20cm between the radiator and your body.

Important Note: This radio module must not installed to co-locate and operating simultaneously with other radios in host system except in accordance with FCC multi-transmitter product procedures. Additional testing and equipment authorization may be required to operating simultaneously with other radio. The availability of some specific channels and/or operational frequency bands are country dependent and are firmware programmed at the factory to match the intended destination. The firmware setting is not accessible by the end user. The host product manufacturer is responsible for compliance to any other FCC rules that apply to the host not covered by the modular transmitter grant of certification. The final host product still requires Part 15 Subpart B compliance testing with the modular transmitter installed. The end user manual shall include all required regulatory information/warning as shown in this manual, including: This product must be installed and operated with a minimum distance of 20 cm between the radiator and user body. This device have got a FCC ID: 2ANDL-WBR3L.The final end product must be labeled in a visible area with the following: “Contains Transmitter Module FCC ID: 2ANDL-WBR3L” This device is intended only for OEM integrators under the following conditions: 1)The antenna must be installed such that 20cm is maintained between the antenna and users, and 2) The transmitter module may not be co-located with any other transmitter or antenna. As long as 2 conditions above are met, further transmitter test will not be required. However, the OEM integrator is still responsible for testing their end-product for any additional compliance requirements required with this module installed.

Declaration of Conformity European notice WBR3L Module Datasheet Hereby, Hangzhou Tuya Information Technology Co., Ltd declares that this module product is in compliance with essential requirements and other relevant provisions of Directive 2014/53/EU, 2011/65/EU. A copy of the Declaration of conformity can be found at https://www.tuya.com.

WBR3L Module Datasheet

This product must not be disposed of as normal household waste, in accordance with EU directive for waste electrical and electronic equipment (WEEE-2012/19/EU). Instead, it should be disposed of by returning it to the point of sale, or to a municipal recycling collection point.

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